This invention relates to a silver halide image that varies in color depending on the viewing condition.
It is known in the art that photographic display materials are utilized for advertising as well as decorative displays of photographic images. Since these display materials are used in advertising, the image quality of the display material is critical in expressing the quality message of the product or service being advertised. Further, a photographic display image needs to be high impact, as it attempts to draw consumer attention to the display material and the desired message being conveyed. Typical applications for display material include product and service advertising in public places such as airports, buses and sports stadiums, movie posters and fine art photography. The desired attributes of a quality, high impact photographic display material are a slight blue density minimum, durability, sharpness and flatness.
Further, prior art display material typically comprises a still image that is backside illuminated. It is widely known that the human eye is sensitive to motion and that the human eye and brain is attracted to motion and thus display materials integrating motion into an display is highly effective method for advertisement. Prior art motion displays typically consist of a series of still illuminated images that are scrolled back and forth on a take up roll.
Prior art silver halide display materials typically utilize yellow, magenta and cyan dyes to create an image. In a typical yellow, magenta and cyan imaging system the color gamut is limited and fixed once the image is exposed and developed. In order to change colors, another display would have to be generated and separately shown.
Bourdelais et al in U.S. Pat. No. 6,030,756 discusses imaging layers containing silver halide and dye forming couplers applied to both sides of a translucent base for a display material. While the display material in U.S. Pat. No. 6,030,756 provides an excellent image that can be displayed without the need for a backlight source, the image color is fixed. There remains a need in the display market to change the color appearance of the display without having to create a new display or to use expensive electronics devices.
McInerney et al in U.S. Pat. Nos. 5,679,139; 5,679,140; 5,679,141; and 5,679,142 teach the shape of preferred subtractive dye absorption shapes for use in four color, C,M,Y,K based ink-jet prints.
McInerney et al in EP 0 825 488 teaches the shape of preferred subtractive cyan dye absorption shape for use in silver halide based color prints.
Kitchin et al in U.S. Pat. No. 4,705,745 teaches the preparation of a photographic element for preparing half-tone color proofs comprising four separate imaging layers capable of producing cyan, magenta, yellow, and black images.
Powers et al in U.S. Pat. No. 4,816,378, teaches an imaging process for the preparation of color half-tone images that contain cyan, magenta, yellow, and black images. The use of the black dye does little to improve the gamut of color reproduction.
Haraga et al in EP 0 915 374 A1 teaches a method for improving image clarity by mixing xe2x80x98invisiblexe2x80x99 information in the original scene with a color print and reproducing it as an infrared dye, magenta dye, or as a mixture of cyan magenta and yellow dyes to achieve improved color tone and realism. The addition of the resulting infrared, magenta, or black dye does little to improve the gamut.
In spite of the foregoing teachings, the coupler sets which have been employed in silver halide color imaging have not provided the ability to change color within the same imaging element. There remains a need to change color based on reflected or transmitted light. Viewing
It has been proposed in U.S. Pat. No. 5,866,282 (Bourdelais et al) to utilize a composite support material with laminated biaxially oriented polyolefin sheets as a photographic imaging material. In U.S. Pat. No. 5,866,282, biaxially oriented polyolefin sheets are extrusion laminated to cellulose paper to create a support for silver halide imaging layers. The biaxially oriented sheets described in U.S. Pat. No. 5,866,282 have a microvoided layer in combination with coextruded layers that contain white pigments such as TiO2 above and below the microvoided layer. In the composite imaging support structure described in U.S. Pat. No. 5,866,282 the silver halide imaging layers are applied to the white, reflecting side of the base that has a spectral transmission less than 15%.
Prior art photographic transmission display materials with incorporated diffusers have light sensitive silver halide emulsions coated directly onto a gelatin coated clear polyester sheet. Incorporated diffusers are necessary to diffuse the light source used to backlight transmission display materials. Without a diffuser, the light source would reduce the quality of the image. Typically, white pigments are coated in the bottom most layer of the imaging layers. Since light sensitive silver halide emulsions tend to be yellow because of the gelatin used, as a binder for photographic emulsions minimum density areas of a developed image will tend to appear yellow. A yellow white reduces the commercial value of a transmission display material because the image viewing public associates image quality with a whiter whites. It would be desirable if a transmission display material with an incorporated diffuser could have a more blue white since a white that is slightly blue is perceptually preferred as the whitest white.
Prior art photographic transmission display materials with incorporated diffusers have light sensitive silver halide emulsions coated directly onto a gelatin subbed clear polyester sheet. TiO2 is added to the bottom most layer of the imaging layers to diffuse light so well that individual elements of the illuminating bulbs utilized are not visible to the observer of the displayed image. However, coating TiO2 in the imaging layer causes manufacturing problems such as increased coating coverage which requires more coating machine drying and a reduction in coating machine productivity as the TiO2 requires additional cleaning of coating machine. Further, as higher amounts of TiO2 are used to diffuse high intensity backlighting systems, the TiO2 coated in the bottom most imaging layer causes unacceptable light scattering reducing the quality of the transmission image. It would be desirable to eliminate the TiO2 from the image layers while providing the necessary transmission properties and image quality properties.
It has been proposed in U.S. Pat. No. 6,017,685 (Bourdelais et al.) to utilize biaxially oriented polyolefin microvoided sheet laminated to polyester for a display base. In U.S. Pat. No. 6,017,685, the incorporated voided layer diffuses the illumination light source avoiding the problems with incorporated TiO2 as a diffuser screen. Disclosed in U.S. Pat. No. 6,017,685 are yellow, magenta and cyan dyes formed by silver halide process and thus the silver halide image disclosed in U.S. Pat. No. 6,017,685 has a limited dye gamut compared to printed inks. Further, the display image disclosed in U.S. Pat. No. 6,017,685 is intended for a still image, one that is inserted into a light frame and projects a uniform, still image.
In has been proposed in U.S. Pat. Nos. 5,689,372; 5,737,087 and 5,639,580 to provide a reflective imaging member that provides motion. While these patents provide an image with a sense of motion they require the use of multiple image layers that have to critically aligned with each other in the presence of a lenticular screen. The motion is generated as the print material is viewed from various angles. While these images provide both depth and motion, they are very expensive to produce and require great skill to properly align the multiple images. There remains a need to for an imaging element that can provide a sense of motion or change in the image without the expense or high level of skill required aligning multiple images.
There is a need for a display imaging material that provides a sense of motion and is capable of changing color.
It is an object of the invention to provide improved imaging layers.
It is another object to provide imaging material that can switch color based on illumination.
It is a further object to maintain processing efficiency of the silver halide image.
It is another object to provide more efficient use of the light used to illuminate transmission display materials.
It is a further object to provide an image with motion.
These and other objects of the invention are accomplished by an imaging element comprising a translucent sheet, and at least three photosensitive dye forming coupler containing layers on the face side of said sheet, wherein said at least three photosensitive forming coupler containing layers comprise a cyan dye forming layer comprising a cyan dye forming coupler in combination with a red sensitized photosensitive emulsion, a yellow dye forming layer comprising a yellow dye forming coupler in combination with a blue light sensitive photosensitive emulsion, a magenta dye forming layer comprising a magenta dye forming coupler and a green light sensitive photosensitive emulsion, and on the back side of said translucent polymer sheet at least one dye forming coupler comprising magenta dye forming coupler, cyan dye forming coupler, or yellow dye forming coupler in combination with a light sensitive silver halide emulsion sensitive to a different wavelength of visible light than it was in combination with on the face side.
The invention provides a display motion imaging material that is color switching capable while maintaining typical the 45-second color development time.